Add to AST location info for compound exception headers or keywords

The location information in the AST for a compound statement spans the whole body.

For example:

>>> src = """with A as cm:
...     1
...     2
...     3
...     """

Output:

"Module(body=[With(items=[withitem(context_expr=Name(id='A', ctx=Load(), lineno=1, col_offset=5, end_lineno=1, end_col_offset=6), optional_vars=Name(id='cm', ctx=Store(), lineno=1, col_offset=10, end_lineno=1, end_col_offset=12))], body=[Expr(value=Constant(value=1, lineno=2, col_offset=4, end_lineno=2, end_col_offset=5), lineno=2, col_offset=4, end_lineno=2, end_col_offset=5), Expr(value=Constant(value=2, lineno=3, col_offset=4, end_lineno=3, end_col_offset=5), lineno=3, col_offset=4, end_lineno=3, end_col_offset=5), Expr(value=Constant(value=3, lineno=4, col_offset=4, end_lineno=4, end_col_offset=5), lineno=4, col_offset=4, end_lineno=4, end_col_offset=5)], lineno=1, col_offset=0, end_lineno=4, end_col_offset=5)])"

If __enter__ or __exit__ of the context manager raises an exception, we don't want the location of the exception to span the entire body. Ideally it would be the location of the with keyword (my view) or the entire with x as y statement (@ericsnowcurrently's view). However, we don't have those locations in the AST so currently we hilight the location of the expression that creates the context manager:

>>> class C:
...     def __enter__(self): 1/0
...     def __exit__(*args): pass
...     
>>> with C() as c: pass
... 
Traceback (most recent call last):
  File "<python-input-11>", line 1, in <module>
    with C() as c: pass
         ~^^
  File "<python-input-10>", line 2, in __enter__
    def __enter__(self): 1/0
                         ~^~
ZeroDivisionError: division by zero

We have similar issue with except blocks and class definitions.

Can we add location information of the keywords, or of the header of a compound expression, to the AST?

@pablogsal @lysnikolaou

Linked PRs

• gh-129162

Aucun fichier source ni test n’est indiqué. Commencez par examiner le comportement des emplacements AST décrit ici et dans le PR lié gh-129162, puis comparez les issues associées aux blocs except et aux définitions de classes. C’est terminé lorsque les en-têtes ou les mots-clés des instructions composées disposent d’emplacements AST exploitables, sans attribuer les exceptions des gestionnaires de contexte à l’ensemble du corps.